What is the primary objective of adding chlorine gas or sodium hypochlorite to municipal drinking water supplies?
Answer and explanation
Correct answer: A. To destroy pathogenic disease-causing micro-organisms and bacteria
- Step 1: Chlorination is a disinfection step in water purification. Step 2. Hypochlorous acid formed by chlorine oxidizes and destroys pathogenic bacteria, viruses, and amoebae. Answer: To destroy pathogenic disease-causing micro-organisms and bacteria. Why not the others: Filtration and sedimentation remove mud; lime neutralizes acidity; chlorine does not add desirable taste.
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